package com.coda.interceptor;

import com.coda.constant.JWTClaimsConstant;
import com.coda.constant.MessageConstant;
import com.coda.context.BaseContext;
import com.coda.exception.BaseException;
import com.coda.properties.JWTProperties;
import com.coda.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Repository;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
public class JwtTokenUserInterceptor implements HandlerInterceptor {

    @Autowired
    private JWTProperties jwtProperties;

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader(jwtProperties.getUserTokenName());
        System.out.println(token);

        //如果token为空拒绝访问
        if (token == null || token.isEmpty()) {
            log.info("JWT 为空，拒绝访问");
            throw new BaseException(MessageConstant.PLEASE_LOGIN);
        }

        //2、校验令牌
        try {
            log.info("jwt校验:{}", token);
            //解析jwt令牌
            Claims claims = JwtUtil.parseJWT(jwtProperties.getUserSecretKey(), token);
            //获取解析出来的id
            Integer id = Integer.valueOf(claims.get(JWTClaimsConstant.ID).toString());
            //如果id为空抛出异常
            if (id == null) {
                throw new BaseException(MessageConstant.USER_NOT_LOGIN_CONTEXT_LOSS);
            }
            log.info("当前员工id：{}", id);
            //获取员工id，存入线程中
            BaseContext.setCurrentId(id);
            //3、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应406状态码
            response.setStatus(HttpServletResponse.SC_NOT_ACCEPTABLE);
            response.setContentType("text/plain;charset=UTF-8");
            response.getWriter().write(MessageConstant.USER_NOT_LOGIN_CONTEXT_LOSS);
            response.getWriter().flush();
            response.getWriter().close();
            return false;
        }
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        BaseContext.removeId();
    }
}
